Li CM, et al. - Experts conducted systematic review with meta-analysis to explore the risk of adverse neonatal outcomes linked with maternal intake of proton pump inhibitor (PPI). They distinguished 26 observational studies (20 cohort, 6 case-control studies), of which 19 assessed PPIs and 12 H2-receptor antagonists (H2RA). They obtained data The obtained data from PubMed, Web of Science, Cochrane Database and Embase. Especially in case-control studies, PPI use was correlated with an elevated risk of congenital malformations. Although H2RA use may be correlated with an increased risk of preterm birth, there were no significant links between PPI use and abortions, stillbirth, neonatal death, preterm birth and low-birth weight. Clinical heterogeneity, information and selection bias may be present in the individual studies, although statistical heterogeneity and the risk of bias were overall low. They observed a link between maternal PPI use and congenital malformations in humans, thus power was insufficient to evaluate specific malformations and drugs.